Electric switch



No Model.) 2 Sheets-Sheet l.

C. G. PERKINS. ELECTRIC SWITCH.

No. 436,107. Patented sept. 9,1890.

(No Model.) 2 Sheets-Sheet 2.v

C. G, PERKINS.`

ELECTRIC SWITCH.

No. 436,107. Patented sept. C, 1890.

- WIM/ESSEC: 5:55 VvE/won ATTORNEY.

UNITED STATES PATENT OFFICE.

CHARLES G. PERKINS, OE HARTFORD, CONNECTICUT.

ELECTRIC SWITCH.

SPECIFICATION forming part of Letters Patent No. 436,107, dated September 9, 1890.

Aptiiauon filed october so, 18:59.

To all whom tema/y concern.-

Be it known that I, CHARLES G. PERKINS, a citizen of the United States, residing at Hartford, in' the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Electric Switches; and I do hereby declare the following to be a full, clear, and exact description of the invention', such as will enable others skilled in the art to which it appertains to make and use the same. C

My invention relates to manual switches,

' and especially to that class in which it is designed to make and break an electrical circuit with a quick and sudden movement, so as to prevent sparking.

The present improvements are concerned with certain details of such a switch, which will be fully described hereinafter, and more particularly pointed out in the claims.

I have illustrated my invention in the accompanying drawings, in which- Figure l is a top view of a switch embodying my invention. Fig. 2 is a similar view with the position of the movable parts reversed. Fig. 3 is a vertical section of my switch. Figs. 4, 5, and 6 are detail views; and Fig.'7 is a horizontal section on the line a: :n of Fig. 3.

Similar letters refer to the same parts in all the drawings.

A is the base of my switch, made of wood, bonsilate, vegetable fiber, or other good insulating material. On the said base are mounted four binding-posts B B B2 B3. The bindingposts are 0f metal, and are normally insulated from each other by air-spaces and by the insulating-base, being arranged in the arc of a circle around the center thereof. Within the binding-posts is located an insulating-plugD of general circular shape, on whose outer surface or periphery are contact-plates d d. The

contact-plates are not rigidly attached to the plug, but are provided with slides e c on opposte sides of the plug which slide in metallicv guides o o', set into the plug, as clearly shown in the drawings. The plates are pressed outward from the plug by springs s s', which are located in apertures within the plug (see Fig. 3) and exert pressure against the plates centrally. The size of the plug and thickness.

Serial No. 328,644. (No model.)

and position of the plates d d are so related to the space between the binding-posts that when the plates are brought into line with the posts the springs ss are put under tension, so as to cause good electrical contact between the plates and the posts. The plug D is loosely mounted on a shaft E, which extends down through the middle of the insulating-base A.

On the same shaft. above the plug -D is loosely mounted an angular metallic block F, which is shown in the present instance in the form of a diamond, which enters an angular opening in the plug D. The opening is of such a shape as to allow considerable play to the points of the diamond. If, however, the diamond is moved beyond the point of lost motion, it carries the block with it, as will appear hereinafter. The upper end of the angular piece is notched or slotted,and a pinf, passing through the shaft E, lies in this slot and has considerable play therein. The outer end of the shaft E is split and slightly spread so as to require the handle I-I to be pressed on when being applied. The handle is provided with notches at the bottom, which catch over a pin g for turning the shaft. Now it is evident that by turning the shaft E through the medium of the handle II the pinfwill soon be brought into contact with the side of the slot in the top of the angular piece. If the motion is continued, the block F will be turned and its points will act in like manner on the block D, thereby turning the plug and the contact-plates CZ d. Now the latter eX- tend far enough around the plug to form bridges between either of the two binding-v posts B and B or B2 or B3, and the plates are so located that when one of pair of posts the other bridges the other pair. Inasmuch as the binding-posts B B form the points of connection for an outgoing electric circuit and the posts B2 B3 form the points of connection for the return-conductors it :is evident when the plates are so-turned as to bridge the binding-posts the circuit Will be complete. In order to prevent the plug from being turned too far in either direction, I provide pins p p', which limit the motion of the plug. The pins are located Within notches on opposite sides of the plug, the play of the plug being limited by the length of these them bridges one' IOC notches. The length is such that when the plug is stopped at one end of its movement the contact-plates d d bridge the respective pairs of binding-posts, and when it is stopped at the other end the said plates are in contact with one only of each pair and are separated by a considerable distance from the other binding-posts.

The devices above described provide in themselves adequate means for making and breaking an electric circuit by turning the shaft E in opposite directions. It is a feature' of importance, however, in devices of this class to provide means for making and breaking the contact by a quick and sudden movement, so as to prevent sparking. To bring about this result I secure to the insulatingblock a pair of posts T T, which support two horizontal spring-arms K K. These springarms stand on opposite sides of the angular block F and tend to resist its being turned. The tops of the posts T T are open, as shown in Fig. 5, and the springs K K are slipped into place after the angular block is mounted. The springs are held in place by catches or projections k 7c', which extend over them at the top of the inner wall of the openings in the post. The construction is such that the springs can be easily removed and replaced, if found necessary. The relation of the parts is such that when the circuit is closed the springs K K hold the angular. block in the position shown in Fig. l. If, now, it is desired toopen the circuit, the shaft E will be turned in the direction of the arrow, thereby bringing the pin f against the sides of the slot in the angular piece. By continuing the motion the block is moved into the position shown in dotted lines in Fig.1, in which position the points of the diamond have just been brought to bear upon the sides of the angular opening in the plug D. Thus far the plug D has not been moved at all. If, however, the shaft be advanced a little farther, the force of the springs K K', acting on the angular surface of the block F, willv throw the latter rapidly around into the position shown in Fig. 2 and carry with it the plug D and the contact-plates d d. In this position the electrical circuit is open, the opening having been accomplished by a quick movement. The sudden turning of the block F produces no jerking on the handle I-I, there being play enough at the points of the angular block and at the pin j to allow for the movement. The motion first given to the block F by turning the shaft E is not communicated to the plug D, but the power eXertedto produce it is stored, so to speak, in the springs K K', and afterward released to produce a sudden movement of the plug.

On the bottom of the shaft E issecured a collar V, on which is an arm t, which extends into a slot or opening t in the bottom of the insulating-base A. The play given to the arm t is of course limited by the length of the arc formed by this slot. In practice I make the length of the slot such that the arm is stopped and the shaft with it before the plug D has reached the limit of its movement in either direction. In this way any unnecessary pressure exerted on the handle II for turning the shaft in the wrong direction or for turning it too hard in the right direction is taken up at the arm t and is not exerted upon the pins p p or at any point Where it might cause injury to the apparatus.

To prevent the spreading and loosening of the contact-plates when breaking the circuit, I have set into the base A a pair o f posts or pins RR,whose function is entirely mechan-4 ical.

The structure described in the foregoing specification I find advantageous, in that it permits the easy detachment of all the parts for repair or renewal. It is only necessary to remove the springs K K and the two pins which pass through the shaft E in order to permit the whole apparatus to be taken apart. The handle can be removed at any time and may thus serve as a key, which an authorized person can carry about with him.

The number of parts is very small and the 'structure is equally adapted to serve for switches carrying a large current or for those carrying a small current. The switch can of course be adapted for a single-pole switch, if desired.

A feature of special importance is the use of detachable contact-plates, which are pressed by springs in the manner described. The removable springs K K are also an advantage.

Having now described my invention, I claiml. In an electric switch, contact making and breaking devices and a cover therefor, a central operating split shaft and a pin traversing it, and a handle adapted to slide on over the shaft, the said handle being notched to fit over the said pin, as described.

2. In an electric switch, a circular insulating plug or holder carrying one or more contact-plates loosely attached to the periphery thereof, and one or more springs which press the contact plate or plates away from the plug or holder, in combination' with one or more contact-pieces co-operating with the springpressed plate or plates, as set forth.

3. In an electric switch, an operating-shaft, a contact-plug loosely mounted thereon, an angular block, also loosely mounted on the shaft, the plug having an angular opening larger than but co-operating with the 'said block, and a pin in the said shaft located in a slot in the said angular block, all in combination with one or more springs pressing against the side or sides of the block, as set forth.

4. The combination, with the angular block IOO IIO

In testimony whereof I have affixed my sig- Io nature in presence of two witnesses.

CHARLES G. PERKINS.

Witnesses:

G. H. STOCKBRIDGE, CHAs. B. SHUMWAY. 

